Vast felling and mulching operations are often performed with heavy-duty brush cutters. These brush cutters generally consist of cutter heads removably or permanently fixed on self-propelled vehicles.
Heavy-duty brush cutter heads generally have a plurality of blade-type cutting teeth or hammer-type cutting elements, either hingedly or fixedly mounted to the body of a horizontal drum or to the lower surface of a horizontal disc. High velocity rotation of the drum or of the disc causes the cutting elements to shred wood, debris and the like.
Blade-type cutter heads tend to have an advantage over hammer-type cutters in that the dispersion of woodchips during the cutting operation tends to be minimized. This tends to create safer working conditions for workers. U.S. Pat. Nos. 6,321,518, 5,975,167 and 5,642,765 disclose brush-cutter heads comprising U-shaped cutters hingedly mounted on a support. However, there tends to be some drawbacks associated with this type of head configuration. In particular, the teeth and their corresponding supports tend to be prone to excessive wear and damage as a result of repeated impact by rocks and other hard debris. In addition, the efficacy of these teeth tends to decline from repeated impact with hard debris.
Typical fixed blade-type cutting teeth are made from a plate-like metal section curved into stirrup-shaped elements, comprising a cutting edge on their leading face. The manufacturing of such cutting elements is relatively quick and inexpensive. For example, U.S. Pat. No. 6,764,035, discloses a brush-cutter head comprising cutting teeth, each tooth being made from a bent plate having a uniform thickness. Although the fixed cutting teeth disclosed in this patent tend to be more robust and exhibit improved wear resistance than the hingedly mounted-type cutting teeth, the fixed cutting teeth must nonetheless be sharpened often. The need for frequent sharpening tends to reduce the cutting efficiency of brush cutters thereby impeding productivity and increasing operation and maintenance costs.
Therefore, it would be advantageous to have a cutter head with teeth that exhibit improved wear resistance characteristics. In particular, teeth which do not require frequent sharpening, repair or replacement would be most desirable.